The increasing number of difficult Extended Reach Drilling (ERD) applications in recent years has emphasized the need for reducing drill string drag. Drill string drag can substantially limit weight on bit and negatively effect directional control.
An improved type of drill pipe deployed Non-Rotating Drill Pipe Protector (NRDPP) has been developed that was found, both in laboratory tests and in actual down-hole drilling/sliding applications, to reduce drag inside casing up to 50% of that for bare drill pipe. This new tool incorporates existing NRDPP fluid bearing technology for torque reduction along with a modified geometry and the use of low-friction wear pads to reduce drag.
This paper describes the design and testing of the new "Low-Drag" NRDPP and provides a detailed discussion of three different wells that were drilled using this new tool for the purpose of providing drag, torque, and casing wear reduction. The wells, drilled by major oil companies in different regions of the world, were of varying profiles and possessed a unique set of operational circumstances.